Ship&#39;s compass.



N0. 668,972. Patented Feb. 26, |90l.

` H BBUNS SHIPS COMPASS.

(Applicltion Bled Oct. 6, 1899.-)

(N0 Nudel.)

nu, wnsnmmon n c lINTTn o STATES HINRICH BRUNS, OF BREMEN, GERMANY.

SHIPS COMPASS.

SPECIFICATION forming part of Letters Patent No. 668,972, dated February 26, 1901.

Application filed October 6, 1899. Serial No. 732,789. (No model.)

To all whom t may concern:

Be it known that I, HINRICH BRUNS, a citizen of the free city of Bremen, residing at Bremen, in the Empire of Germany, have invented certain new and useful Improvements in Ships Compasses, (for which I have applied for a patent in Germany, dated March 9, 1899,) of which the following is a specification.

Compasses as hitherto used do not enable an exact course to be steered whenever the course lies between two divisions on the compass-card---vl e., when it does not lie through the principal points of the card-and in such cases 'the helmsman has to rely upon the judgment of his eye for the measurement of the fractional part of a marked division. My present invention is designed to enable the heltnsman to avoid deviating from the true course, caused by the above difliculty, and to steer a true course without tiring his eye. For this purpose an adjustable plate is provided on the compass-casing, which plate has an auxiliary steering line or point which can be adjusted to the right or left of the fixed steering line or point and can be used instead of the latter whenever the course is such that it cannot be read exactly on the compass-card.

The invention is illustrated in the accompanying drawings.

Figure l is a plan. Fig. 2 is a sectional View on the line ly g of Fig. 1, and Fig. 3 is a sectional view on the line 0c x of Fig. l.

At the present time it is usual to steer according to the points of the compass, with the assistance of the steering-point or lubbers mark a.

It has been the desire of many seamen, particularly on fast-going ships, to determine the course exactly in degrees and to steer accordingly. The great objection to this is that the helmsman cannot see the degree-scale sufficiently clearly on the compass-cards at present in use and cannot steer thereby. In carrying out my invention I use a card divided from north and south to east and west in such a manner that only each full five and ten de gree division is visible. I retain the eight main points of the compass, but omit the intermediate points, (one-fourth, one-half, and one-third points.)

In the accompanying drawings, bis the compass-casing, and a is the fixed steering-point, on both sides of which there are divisional marks l and 2, respectively.

c is a plate having a cut-.out portion c' and steering line or point d. This plate can be adjusted by means of a screw g, passing through a short slotf in the compass-casing.

To explain the manner of using my invention, I give the following examples:

When, for instance, it is desired to steer south eighty-seven degrees east, which degree is not marked on the compass, the steering line or point d is adjusted two degrees t-o the right of the middle line or point and the helmsman is ordered south eighty-live degrees east, which is marked. This steered course being two degrees to the right of the direction of the keel of the ship, the real course is south eighty-seven degrees east.

If the west magnetic deviation increases, for instance, one degree south, eighty-six degrees east must be steered in order to keep to the true course. The steering line or point is adj usted one degree to the left from its previous position, so that it is only 011e degree to the right of the middle line or point, and the steered course remains south eighty-five de grees east, which is then one degree to the right of the direction of the keel of the ship and the direction is therefore south eightysix degrees east.

If the west magnetic deviation had de creased one degree, the direction would be south eighty-eight degrees east in order to adhere to the true course. This is effected by adjusting the movable steering line or point two degrees to the left of the middle line or point, thus steering east.

In order to go in the direction of a tive degree or ten degree course, the steering line or point is placed in the middle and' the corresponding course is ordered. The steering line or point is adjusted to the right or left of the fixed steering-line a distance corresponding to the difference between the real course and the imaginary or steered course. For example, if the real course is north fifty-two degrees east then the steering course is north fifty degrees east and the steering-line is moved two degrees to the left. If the real course is south eighty-three degrees west, then the steering course is south eighty-five de- IOO grecs west and the steering-line is moved two degrees to the right. If the real course is north eight degrees West, then the steering course is north ten degrees west and the steering-line is moved two degrees to the right. If the real course is south Sixty degrees east, then th e steering oou rse is south sixty degrees east and the steering-line is moved to the middle.

I am aware that adjustable indicators have been already provided on mariners coinpasses; but such indicators have been used only to mark the direction to some place or to facilitate the reading of of the position of the ship. My improved device, however, which is only adjustable to a length corresponding to ve degrees, facilitates the steering of a ship according to degrees and enables the helmsman to steer With absolute accuracy, even when the course lies between two divisions on the Compass-card, Without tiring his eye.

What I claim, and desire to secure by Letters Patent of the United States, is-

In a inariners compass, the combination with the .compass-box having,` its fixed steering point or lubbers mark, and with the inagnetic card having the points of the compass thereon, of a steering-plate with an auxiliary steering-mark thereon, said plate being adjustably mounted on the compass-box independently of the card and in immediate proximity of the lubbers mark of the box, for the purpose speeied.

' In testimony whereof I have hereunto set my hand in the presence of two witnesses. HINRICH BRUNS.

Witnesses:

P. NIETJEN, C. ANDERsEN. 

